Acupuncture is one of the most promising alternative therapeutic methods. Although there does not yet exist a broad consensus as to the basic mechanisms underlying acupuncture action, the central nervous system (CNS) is arguably the most important mediator of acupuncture's multifaceted effects on the body. While acupuncture has been reported to modulate multiple systems of the body (autonomic, immunological, cardiovascular etc.), most studies of acupuncture have focused on pain analgesia. We propose that acupuncture modulation of the autonomic nervous system can be investigated by multi-modal techniques combining functional MRI with physiological monitoring. Electrocardiography (ECG) and pupilometry will be recorded simultaneously with fMRI. ECG data can be used to infer autonomic tone to the heart through heart rate variability (HRV), while pupil size variability (PSV) can be used to measure autonomic tone to the eye. Both physiological measures will be integrated with fMRI data to derive autonomic associated brain response resulting from acupuncture. Once our multimodal platform is proven robust and has been validated, we will explore the central network for acupuncture ANS modulation and potential laterality in acupoint response.